Untitled

clearvars
freq = 50;
% https://www.mathworks.com/help/matlab/ref/fft.html
Fs = 1000;            % Sampling frequency                    
T = 1/Fs;             % Sampling period       
L = 1500;             % Length of signal
t = (0:L-1)*T;        % Time vector
f = Fs*(0:(L/2))/L;

% Beautiful square: theta redefined

theta = linspace(-2*pi, 2*pi, 1e5);

x1 = square(theta);

x2 = square(theta + deg2rad(15))/2 + square(theta - deg2rad(15))/2;

figure()

hold on

plot(theta/pi, x1)

plot(theta/pi, x2)

xlabel('\theta (\times\pi rad)')

ylabel('MMF (Ni/2)')

hold off

% FFT calculation

theta = 2*pi*freq*t;

% theta = linspace(-2*pi, 2*pi, 1e5)

figure()

hold on

x1 = square(theta);

Y = fft(x1);

P2 = abs(Y/L);

P1 = P2(1:L/2+1);

P1(2:end-1) = 2*P1(2:end-1);

plot(f, P1)

x2 = square(theta + deg2rad(15))/2 + square(theta - deg2rad(15))/2;

Y = fft(x2);

P2 = abs(Y/L);

P1 = P2(1:L/2+1);

P1(2:end-1) = 2*P1(2:end-1);

plot(f, P1)

xlabel('f (Hz)')

ylabel('|P1(f)|')

% Original plot

figure()

hold on

plot(theta/pi, x1)

plot(theta/pi, x2)

xlim([0, 4])

hold off

xlabel('\theta (\times\pi rad)')

ylabel('MMF (Ni/2)')

hold off